No doubt England and how you guys can grow things in small places is an inspiration to the new BYOC (back yard orchard culture)
movement here in the states. Check out these videos. Start with the most recent (summer pruning fruit trees 2013) as Tom is shown trimming a small fruit tree hedge. Sounds exactly what you need.

Here is a link that might be useful: Tom Wilson nursery videos

Will Columnar Apples work there?Otherwise,yeah,a fair amount of pruning will need to be done. Brady

You would be surprised what you can fit into small spaces. This is the back yard with about 120 different species and roughly 15 trees of various ages.

I think the main issue will be that the border is North facing and overshadowed by neighbouring shrubs from the South, not that the space is restricted. Not to mention that huge oak tree in the corner. I would recommend you research growing fruit in small spaces but also consult reputable growers for suitable cultivars for those conditions. If you can get to Wisley have a look at the demonstration gardens. There are some very compact fruit plots. Certainly don't just get whatever Homebase has this week. These guys are pretty good.

Here is a link that might be useful: Fruit Trees

Thanks for the replies folks - keep them coming - let's have some fruity brainstorming!
I've realised that the idea I had in mind was poorly conveyed in the posting (and especially the diagram.) Here's goes with another attempt... and another poor diagram!

My standard tree idea was to have the clear stem out of the light and the top branch sytem (leaves & fruit) to be in sunlight. This may encourage some fruit to form and possibly ripen. The stem section may be wasted, but it does not get enough direct sun to allow fruiting from low down to high up, as most trained fruit has (cordons, fans espaliers.) However, the idea of a tree trained to be like a tall step-over (one tier espalier) might work, but it wastes a lot lot of space and would need some training! A big T - tall stem and long laterals. It will also look "ahem" bizarre (no laughing please.) I would ideally like the overall height of the tree to be around 4m and pruned so that most of thefruiting branches hang over my side of the fence. Don't mind climbing a ladder. I used to go up an old apple bush tree that had an open goblet shape that had a 1m tall stem in my old garden. That tree would do well in this situation if I removed the brances that would push into the fence.
Regarding varieties I've tasted and enjoyed: Apples - Sunset, Egremont Russet, Discovery, Scrumptious, Spartan, Fiesta, Red Falstaff. Pears - Comice, Concorde, Beth, Conference, Williams. Plums - Jubilee, Opal, Victoria, Green Gage, Ouillins Gage. Currently I'm thinking of 2 apple trees, 2 pear trees and forgoing plums for lack of space and ripening conditions. As I don't want any culinary only varieties, and if desert varieties are difficult in semi-shade or sun for only half the day, then how about dual purpose variety as a compromise. Then it could be left to ripen for longer and eaten as a desert. Or maybe planting early varieties and just leaving them to get sun for longer and picking later. Suagrs may have developed by then.

You could build a raised bed a couple feet tall, which would help bring your plants up into the sunlight without looking strange with a super high T type step-over.

I have a ton of plants growing in a very small area, and found that if I alternate tree-bush-tree-bush, I can fit almost double the amount of plants without any of them blocking sunlight from each other. I train the trees' canopy to occupy the area above the bushes next to the tree. Like: YoYoYoYoY - if you imagine the Ys as trees and Os as bushes and being crammed closer together. This would allow you to utilize the space around the tall tree stem.

Also, my experience is that most fruit bushes tolerate shade better than trees.